| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a lithium ion secondary battery having a great charge/discharge capacity while reducing the loss of materials. <P>SOLUTION: The lithium ion secondary battery includes a solid electrolyte layer 1 including inorganic solid electrolyte, a negative electrode 2 including metal lithium, and a positive electrode 3. When a charge/discharge cycle is carried out at a current density of 0.2 mA/cm<SP>2</SP>, W<SB>10</SB>/W<SB>1</SB>×100≥80 is satisfied, where W<SB>1</SB>is a first discharge capacity, and W<SB>10</SB>is tenth discharge capacity. A buffer layer 4 including a lithium ion conductive polymer is provided between the solid electrolyte layer 1 and the negative electrode 2. <P>COPYRIGHT: (C)2011,JPO&INPIT |
